.wordsWrapper {
    width: 100vw;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    flex-shrink: 0;
    user-select: none;
}
.userInfoRow {
    text-align: center;
    margin-top: 30px;
    cursor: pointer;
}
.wordsCard {
    position: relative;
}
.cardBox {
    margin-top: 40px;
    width: 75%;
    height: 68%;
    border: 1px solid #e1e1e1;
    margin-left: 12.5%;
    display: flex;
    overflow: hidden;
}
.cardList {
    width: 100%;
    height: 100%;
    display: flex;
    transition: transform linear 0.3s;
}
.operateBtns {
    display: flex;
    justify-content: center;
    margin-top: 3vh;
}
.operateBtns > div + div {
    margin-left: 8px;
}
.wordCard {
    width: 100%;
    height: 100%;
    flex-shrink: 0;
    position: relative;
    transition: transform linear 0.4s;
    box-shadow: 0 0 3px 3px #00000030;
}
.wordCard + .wordCard {
    margin-left: 8px;
}
.wordCardFront {
    font-weight: bold;
    font-size: 30px;
    position: relative;
    z-index: 2;
    background-color: #fff;
}
.wordCardFront,
.wordCardBack {
    width: calc(100% - 2px);
    height: calc(100% - 2px);
    display: flex;
    justify-content: center;
    align-items: center;
}
.wordCardBack {
    position: absolute;
    top: 0;
    transform: rotateY(180deg);
    z-index: 1;
    background-color: #fff;
    transition: z-index linear 0.4s;
}
.previous,
.next {
    width: 3vw;
    height: 3vw;
    min-width: 24px;
    min-height: 24px;
    max-width: 45px;
    max-height: 45px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    flex-shrink: 0;
    background-image: url(../../assets/imgs/next.svg);
    background-size: 50% 50%;
    background-color: #cccccc;
    background-repeat: no-repeat;
    background-position: center;
    position: absolute;
    top: 46%;
    cursor: pointer;
}
.previous:active,
.next:active {
    box-shadow: 0 0 4px 4px #00000012;
}
.disabledChangeBtn {
    background-color: #f5f5f5;
    cursor: not-allowed;
}
.disabledChangeBtn:active {
    box-shadow: none;
}
.previous {
    transform: rotate(180deg);
    left: 3%;
}
.next {
    right: 3%;
}
.emptyContentTips,
.emptyWordTips {
    font-size: 14px;
    width: 100%;
    color: #ccc;
    text-align: center;
}
.emptyWordTips {
    margin-top: 140px;
}
